An image that has been captured by an image capturing apparatus is constituted by a plurality of pixels. The overall image is formed using color or density that the pixels represent. However, pixels called anomalous pixels exist among the plurality of pixels. Anomalous pixels are defective pixels having outputs that deviate from an output range which is determined for a predetermined input in advance because of abnormalities of circuits or elements included in the image capturing apparatus, or the like, or pixels having values indicating other abnormalities or failures. Because the anomalous pixels influence the image quality of the captured image, the anomalous pixels are corrected, for example, using a method for replacing the anomalous pixels using the average pixel values of pixels surrounding the anomalous pixels or the like. An image in which the anomalous pixels are corrected is provided for a user.
Furthermore, the positions of anomalous pixels change in accordance with anomalous-pixel acquisition schemes, such as image capture schemes for images and schemes for extracting anomalous pixels from the images. As a technology for correcting anomalous pixels, in Japanese Patent Laid-Open No. 2000-101925, a technology for correcting the positions of anomalous pixels that change in accordance with image capture schemes performed by an image capturing apparatus is disclosed. In Japanese Patent Laid-Open No. 2004-187163, a technology for extracting anomalous pixels that differ in accordance with the gain of a circuit system, and for correcting the anomalous pixels is disclosed.
On the other hand, for example, in medical fields, there is a demand for checking of positions at which anomalous pixels that were subjected to a correction process existed. The reason for this is that, because pixel values of the anomalous pixels have been changed by performing the correction process on the anomalous pixels, it is necessary to check the original image. In Japanese Patent Laid-Open No. 2001-8928, a technology for displaying the positions of anomalous pixels that exist in a region which a user selects in a fluoroscopic image is disclosed. However, in display of anomalous pixels that is disclosed in Japanese Patent Laid-Open No. 2001-8928, a fact that the positions of anomalous pixels change in accordance with anomalous-pixel acquisition schemes is not considered. In the technologies described in the above-mentioned Japanese Patent Laid-Open No. 2000-101925 and Japanese Patent Laid-Open No. 2004-187163, the differences among acquisition schemes are considered. However, the technologies described in the above-mentioned Japanese Patent Laid-Open No. 2001-8928 and Japanese Patent Laid-Open No. 2000-101925 are technologies that relate to correction processes for causing anomalous pixels to disappear, and technologies that conflict with display of anomalous pixels.
Thus, in the related art, in a case in which a plurality of anomalous-pixel acquisition schemes are utilized, such as a case in which a plurality of image capture schemes or a plurality of schemes for extracting anomalous pixels exist, there is no technology for meeting a demand for comparison and checking of the positions of anomalous pixels that change on an acquisition-scheme-by-acquisition-scheme basis.